... Small spark,safe BOSCH 91111 BSX 172-173 2-BS 172-173 ,dynastart carbon brush,starter carbon brush, ... rough, ablation and so on. (2) With a good flow properties and set to change commutation , so ... surface of commutator or collector ring quickly form a uniform, moderate and stable oxide film. Non- ... burning. Carbon Brushes Description The Principal Dimensions of a Carbon Brush Note: We work to NEMA and ...